The invention relates to a continuously operating mixing kneader for the thermal treatment of products in liquid, pasty and/or pulverulent state in a housing, there being arranged in this housing, running axially and concentrically, a kneader shaft, which is fitted with disk elements and kneading bars, rotates about an axis of rotation and effects the transporting of the product in the direction of transport, and there being provided between the disk elements kneading counter-elements, fixed to the housing, the disk elements being arranged furthermore in disk planes perpendicularly to the kneader shaft and forming between them free sectors, which create kneading chambers with the disk plane of adjacent disk elements.
A generally horizontal mixing kneader normally operates at average product filling levels of between 50% and 80%. This makes it possible to supply or remove gases or vapors during the process.
The basic idea of such a mixing kneader is set out in German Patent Specification 2,349,106. There, a mixing kneader of the abovementioned type is presented, in which disk elements and kneading counter-elements interact very favorably to improve the mixing and kneading action as well as to clean the individual elements Due to the inclined position of individual elements, the axial transporting action is also favorably influenced. However, it has been found that, in spite of the kneading counter-elements, a certain torus formation is possible in the chamber, between two disk planes, that is to say that the product remains at a standstill in the kneading chamber and is not kneaded. In order to counteract this torus formation, German Offenlegungsschrift 3,704,268, for example, already shows transport elements which transport the product better due to an inclined position of a transport bar.
The same also applies to the mixer arms according to German Offenlegungsschrift 3,538,070, which merely provide an additional rearrangement of the layers and intermixing.